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v4.6
  1/*
  2 * Many of the syscalls used in this file expect some of the arguments
  3 * to be __user pointers not __kernel pointers.  To limit the sparse
  4 * noise, turn off sparse checking for this file.
  5 */
  6#ifdef __CHECKER__
  7#undef __CHECKER__
  8#warning "Sparse checking disabled for this file"
  9#endif
 10
 11#include <linux/init.h>
 12#include <linux/fs.h>
 13#include <linux/slab.h>
 14#include <linux/types.h>
 15#include <linux/fcntl.h>
 16#include <linux/delay.h>
 17#include <linux/string.h>
 18#include <linux/dirent.h>
 19#include <linux/syscalls.h>
 20#include <linux/utime.h>
 
 21
 22static ssize_t __init xwrite(int fd, const char *p, size_t count)
 23{
 24	ssize_t out = 0;
 25
 26	/* sys_write only can write MAX_RW_COUNT aka 2G-4K bytes at most */
 27	while (count) {
 28		ssize_t rv = sys_write(fd, p, count);
 29
 30		if (rv < 0) {
 31			if (rv == -EINTR || rv == -EAGAIN)
 32				continue;
 33			return out ? out : rv;
 34		} else if (rv == 0)
 35			break;
 36
 37		p += rv;
 38		out += rv;
 39		count -= rv;
 40	}
 41
 42	return out;
 43}
 44
 45static __initdata char *message;
 46static void __init error(char *x)
 47{
 48	if (!message)
 49		message = x;
 50}
 51
 52/* link hash */
 53
 54#define N_ALIGN(len) ((((len) + 1) & ~3) + 2)
 55
 56static __initdata struct hash {
 57	int ino, minor, major;
 58	umode_t mode;
 59	struct hash *next;
 60	char name[N_ALIGN(PATH_MAX)];
 61} *head[32];
 62
 63static inline int hash(int major, int minor, int ino)
 64{
 65	unsigned long tmp = ino + minor + (major << 3);
 66	tmp += tmp >> 5;
 67	return tmp & 31;
 68}
 69
 70static char __init *find_link(int major, int minor, int ino,
 71			      umode_t mode, char *name)
 72{
 73	struct hash **p, *q;
 74	for (p = head + hash(major, minor, ino); *p; p = &(*p)->next) {
 75		if ((*p)->ino != ino)
 76			continue;
 77		if ((*p)->minor != minor)
 78			continue;
 79		if ((*p)->major != major)
 80			continue;
 81		if (((*p)->mode ^ mode) & S_IFMT)
 82			continue;
 83		return (*p)->name;
 84	}
 85	q = kmalloc(sizeof(struct hash), GFP_KERNEL);
 86	if (!q)
 87		panic("can't allocate link hash entry");
 88	q->major = major;
 89	q->minor = minor;
 90	q->ino = ino;
 91	q->mode = mode;
 92	strcpy(q->name, name);
 93	q->next = NULL;
 94	*p = q;
 95	return NULL;
 96}
 97
 98static void __init free_hash(void)
 99{
100	struct hash **p, *q;
101	for (p = head; p < head + 32; p++) {
102		while (*p) {
103			q = *p;
104			*p = q->next;
105			kfree(q);
106		}
107	}
108}
109
110static long __init do_utime(char *filename, time_t mtime)
111{
112	struct timespec t[2];
113
114	t[0].tv_sec = mtime;
115	t[0].tv_nsec = 0;
116	t[1].tv_sec = mtime;
117	t[1].tv_nsec = 0;
118
119	return do_utimes(AT_FDCWD, filename, t, AT_SYMLINK_NOFOLLOW);
120}
121
122static __initdata LIST_HEAD(dir_list);
123struct dir_entry {
124	struct list_head list;
125	char *name;
126	time_t mtime;
127};
128
129static void __init dir_add(const char *name, time_t mtime)
130{
131	struct dir_entry *de = kmalloc(sizeof(struct dir_entry), GFP_KERNEL);
132	if (!de)
133		panic("can't allocate dir_entry buffer");
134	INIT_LIST_HEAD(&de->list);
135	de->name = kstrdup(name, GFP_KERNEL);
136	de->mtime = mtime;
137	list_add(&de->list, &dir_list);
138}
139
140static void __init dir_utime(void)
141{
142	struct dir_entry *de, *tmp;
143	list_for_each_entry_safe(de, tmp, &dir_list, list) {
144		list_del(&de->list);
145		do_utime(de->name, de->mtime);
146		kfree(de->name);
147		kfree(de);
148	}
149}
150
151static __initdata time_t mtime;
152
153/* cpio header parsing */
154
155static __initdata unsigned long ino, major, minor, nlink;
156static __initdata umode_t mode;
157static __initdata unsigned long body_len, name_len;
158static __initdata uid_t uid;
159static __initdata gid_t gid;
160static __initdata unsigned rdev;
161
162static void __init parse_header(char *s)
163{
164	unsigned long parsed[12];
165	char buf[9];
166	int i;
167
168	buf[8] = '\0';
169	for (i = 0, s += 6; i < 12; i++, s += 8) {
170		memcpy(buf, s, 8);
171		parsed[i] = simple_strtoul(buf, NULL, 16);
172	}
173	ino = parsed[0];
174	mode = parsed[1];
175	uid = parsed[2];
176	gid = parsed[3];
177	nlink = parsed[4];
178	mtime = parsed[5];
179	body_len = parsed[6];
180	major = parsed[7];
181	minor = parsed[8];
182	rdev = new_encode_dev(MKDEV(parsed[9], parsed[10]));
183	name_len = parsed[11];
184}
185
186/* FSM */
187
188static __initdata enum state {
189	Start,
190	Collect,
191	GotHeader,
192	SkipIt,
193	GotName,
194	CopyFile,
195	GotSymlink,
196	Reset
197} state, next_state;
198
199static __initdata char *victim;
200static unsigned long byte_count __initdata;
201static __initdata loff_t this_header, next_header;
202
203static inline void __init eat(unsigned n)
204{
205	victim += n;
206	this_header += n;
207	byte_count -= n;
208}
209
210static __initdata char *vcollected;
211static __initdata char *collected;
212static long remains __initdata;
213static __initdata char *collect;
214
215static void __init read_into(char *buf, unsigned size, enum state next)
216{
217	if (byte_count >= size) {
218		collected = victim;
219		eat(size);
220		state = next;
221	} else {
222		collect = collected = buf;
223		remains = size;
224		next_state = next;
225		state = Collect;
226	}
227}
228
229static __initdata char *header_buf, *symlink_buf, *name_buf;
230
231static int __init do_start(void)
232{
233	read_into(header_buf, 110, GotHeader);
234	return 0;
235}
236
237static int __init do_collect(void)
238{
239	unsigned long n = remains;
240	if (byte_count < n)
241		n = byte_count;
242	memcpy(collect, victim, n);
243	eat(n);
244	collect += n;
245	if ((remains -= n) != 0)
246		return 1;
247	state = next_state;
248	return 0;
249}
250
251static int __init do_header(void)
252{
253	if (memcmp(collected, "070707", 6)==0) {
254		error("incorrect cpio method used: use -H newc option");
255		return 1;
256	}
257	if (memcmp(collected, "070701", 6)) {
258		error("no cpio magic");
259		return 1;
260	}
261	parse_header(collected);
262	next_header = this_header + N_ALIGN(name_len) + body_len;
263	next_header = (next_header + 3) & ~3;
264	state = SkipIt;
265	if (name_len <= 0 || name_len > PATH_MAX)
266		return 0;
267	if (S_ISLNK(mode)) {
268		if (body_len > PATH_MAX)
269			return 0;
270		collect = collected = symlink_buf;
271		remains = N_ALIGN(name_len) + body_len;
272		next_state = GotSymlink;
273		state = Collect;
274		return 0;
275	}
276	if (S_ISREG(mode) || !body_len)
277		read_into(name_buf, N_ALIGN(name_len), GotName);
278	return 0;
279}
280
281static int __init do_skip(void)
282{
283	if (this_header + byte_count < next_header) {
284		eat(byte_count);
285		return 1;
286	} else {
287		eat(next_header - this_header);
288		state = next_state;
289		return 0;
290	}
291}
292
293static int __init do_reset(void)
294{
295	while (byte_count && *victim == '\0')
296		eat(1);
297	if (byte_count && (this_header & 3))
298		error("broken padding");
299	return 1;
300}
301
302static int __init maybe_link(void)
303{
304	if (nlink >= 2) {
305		char *old = find_link(major, minor, ino, mode, collected);
306		if (old)
307			return (sys_link(old, collected) < 0) ? -1 : 1;
 
 
 
308	}
309	return 0;
310}
311
312static void __init clean_path(char *path, umode_t fmode)
313{
314	struct stat st;
315
316	if (!sys_newlstat(path, &st) && (st.st_mode ^ fmode) & S_IFMT) {
317		if (S_ISDIR(st.st_mode))
318			sys_rmdir(path);
319		else
320			sys_unlink(path);
321	}
 
322}
323
324static __initdata int wfd;
325
326static int __init do_name(void)
327{
328	state = SkipIt;
329	next_state = Reset;
330	if (strcmp(collected, "TRAILER!!!") == 0) {
331		free_hash();
332		return 0;
333	}
334	clean_path(collected, mode);
335	if (S_ISREG(mode)) {
336		int ml = maybe_link();
337		if (ml >= 0) {
338			int openflags = O_WRONLY|O_CREAT;
339			if (ml != 1)
340				openflags |= O_TRUNC;
341			wfd = sys_open(collected, openflags, mode);
342
343			if (wfd >= 0) {
344				sys_fchown(wfd, uid, gid);
345				sys_fchmod(wfd, mode);
346				if (body_len)
347					sys_ftruncate(wfd, body_len);
348				vcollected = kstrdup(collected, GFP_KERNEL);
349				state = CopyFile;
350			}
351		}
352	} else if (S_ISDIR(mode)) {
353		sys_mkdir(collected, mode);
354		sys_chown(collected, uid, gid);
355		sys_chmod(collected, mode);
356		dir_add(collected, mtime);
357	} else if (S_ISBLK(mode) || S_ISCHR(mode) ||
358		   S_ISFIFO(mode) || S_ISSOCK(mode)) {
359		if (maybe_link() == 0) {
360			sys_mknod(collected, mode, rdev);
361			sys_chown(collected, uid, gid);
362			sys_chmod(collected, mode);
363			do_utime(collected, mtime);
364		}
365	}
366	return 0;
367}
368
369static int __init do_copy(void)
370{
371	if (byte_count >= body_len) {
372		if (xwrite(wfd, victim, body_len) != body_len)
373			error("write error");
374		sys_close(wfd);
375		do_utime(vcollected, mtime);
376		kfree(vcollected);
377		eat(body_len);
378		state = SkipIt;
379		return 0;
380	} else {
381		if (xwrite(wfd, victim, byte_count) != byte_count)
382			error("write error");
383		body_len -= byte_count;
384		eat(byte_count);
385		return 1;
386	}
387}
388
389static int __init do_symlink(void)
390{
391	collected[N_ALIGN(name_len) + body_len] = '\0';
392	clean_path(collected, 0);
393	sys_symlink(collected + N_ALIGN(name_len), collected);
394	sys_lchown(collected, uid, gid);
395	do_utime(collected, mtime);
396	state = SkipIt;
397	next_state = Reset;
398	return 0;
399}
400
401static __initdata int (*actions[])(void) = {
402	[Start]		= do_start,
403	[Collect]	= do_collect,
404	[GotHeader]	= do_header,
405	[SkipIt]	= do_skip,
406	[GotName]	= do_name,
407	[CopyFile]	= do_copy,
408	[GotSymlink]	= do_symlink,
409	[Reset]		= do_reset,
410};
411
412static long __init write_buffer(char *buf, unsigned long len)
413{
414	byte_count = len;
415	victim = buf;
416
417	while (!actions[state]())
418		;
419	return len - byte_count;
420}
421
422static long __init flush_buffer(void *bufv, unsigned long len)
423{
424	char *buf = (char *) bufv;
425	long written;
426	long origLen = len;
427	if (message)
428		return -1;
429	while ((written = write_buffer(buf, len)) < len && !message) {
430		char c = buf[written];
431		if (c == '0') {
432			buf += written;
433			len -= written;
434			state = Start;
435		} else if (c == 0) {
436			buf += written;
437			len -= written;
438			state = Reset;
439		} else
440			error("junk in compressed archive");
441	}
442	return origLen;
443}
444
445static unsigned long my_inptr; /* index of next byte to be processed in inbuf */
446
447#include <linux/decompress/generic.h>
448
449static char * __init unpack_to_rootfs(char *buf, unsigned long len)
450{
451	long written;
452	decompress_fn decompress;
453	const char *compress_name;
454	static __initdata char msg_buf[64];
455
456	header_buf = kmalloc(110, GFP_KERNEL);
457	symlink_buf = kmalloc(PATH_MAX + N_ALIGN(PATH_MAX) + 1, GFP_KERNEL);
458	name_buf = kmalloc(N_ALIGN(PATH_MAX), GFP_KERNEL);
459
460	if (!header_buf || !symlink_buf || !name_buf)
461		panic("can't allocate buffers");
462
463	state = Start;
464	this_header = 0;
465	message = NULL;
466	while (!message && len) {
467		loff_t saved_offset = this_header;
468		if (*buf == '0' && !(this_header & 3)) {
469			state = Start;
470			written = write_buffer(buf, len);
471			buf += written;
472			len -= written;
473			continue;
474		}
475		if (!*buf) {
476			buf++;
477			len--;
478			this_header++;
479			continue;
480		}
481		this_header = 0;
482		decompress = decompress_method(buf, len, &compress_name);
483		pr_debug("Detected %s compressed data\n", compress_name);
484		if (decompress) {
485			int res = decompress(buf, len, NULL, flush_buffer, NULL,
486				   &my_inptr, error);
487			if (res)
488				error("decompressor failed");
489		} else if (compress_name) {
490			if (!message) {
491				snprintf(msg_buf, sizeof msg_buf,
492					 "compression method %s not configured",
493					 compress_name);
494				message = msg_buf;
495			}
496		} else
497			error("junk in compressed archive");
498		if (state != Reset)
499			error("junk in compressed archive");
500		this_header = saved_offset + my_inptr;
501		buf += my_inptr;
502		len -= my_inptr;
503	}
504	dir_utime();
505	kfree(name_buf);
506	kfree(symlink_buf);
507	kfree(header_buf);
508	return message;
509}
510
511static int __initdata do_retain_initrd;
512
513static int __init retain_initrd_param(char *str)
514{
515	if (*str)
516		return 0;
517	do_retain_initrd = 1;
518	return 1;
519}
520__setup("retain_initrd", retain_initrd_param);
521
 
 
 
 
 
 
 
 
 
522extern char __initramfs_start[];
523extern unsigned long __initramfs_size;
524#include <linux/initrd.h>
525#include <linux/kexec.h>
526
527static void __init free_initrd(void)
528{
 
 
 
 
529#ifdef CONFIG_KEXEC_CORE
 
 
530	unsigned long crashk_start = (unsigned long)__va(crashk_res.start);
531	unsigned long crashk_end   = (unsigned long)__va(crashk_res.end);
532#endif
533	if (do_retain_initrd)
534		goto skip;
535
536#ifdef CONFIG_KEXEC_CORE
537	/*
538	 * If the initrd region is overlapped with crashkernel reserved region,
539	 * free only memory that is not part of crashkernel region.
540	 */
541	if (initrd_start < crashk_end && initrd_end > crashk_start) {
542		/*
543		 * Initialize initrd memory region since the kexec boot does
544		 * not do.
545		 */
546		memset((void *)initrd_start, 0, initrd_end - initrd_start);
547		if (initrd_start < crashk_start)
548			free_initrd_mem(initrd_start, crashk_start);
549		if (initrd_end > crashk_end)
550			free_initrd_mem(crashk_end, initrd_end);
551	} else
552#endif
553		free_initrd_mem(initrd_start, initrd_end);
554skip:
555	initrd_start = 0;
556	initrd_end = 0;
557}
 
 
 
 
 
 
558
559#ifdef CONFIG_BLK_DEV_RAM
560#define BUF_SIZE 1024
561static void __init clean_rootfs(void)
562{
563	int fd;
564	void *buf;
565	struct linux_dirent64 *dirp;
566	int num;
567
568	fd = sys_open("/", O_RDONLY, 0);
569	WARN_ON(fd < 0);
570	if (fd < 0)
571		return;
572	buf = kzalloc(BUF_SIZE, GFP_KERNEL);
573	WARN_ON(!buf);
574	if (!buf) {
575		sys_close(fd);
576		return;
577	}
578
579	dirp = buf;
580	num = sys_getdents64(fd, dirp, BUF_SIZE);
581	while (num > 0) {
582		while (num > 0) {
583			struct stat st;
584			int ret;
585
586			ret = sys_newlstat(dirp->d_name, &st);
587			WARN_ON_ONCE(ret);
588			if (!ret) {
589				if (S_ISDIR(st.st_mode))
590					sys_rmdir(dirp->d_name);
591				else
592					sys_unlink(dirp->d_name);
593			}
594
595			num -= dirp->d_reclen;
596			dirp = (void *)dirp + dirp->d_reclen;
597		}
598		dirp = buf;
599		memset(buf, 0, BUF_SIZE);
600		num = sys_getdents64(fd, dirp, BUF_SIZE);
601	}
602
603	sys_close(fd);
604	kfree(buf);
605}
606#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
607
608static int __init populate_rootfs(void)
609{
 
610	char *err = unpack_to_rootfs(__initramfs_start, __initramfs_size);
611	if (err)
612		panic("%s", err); /* Failed to decompress INTERNAL initramfs */
613	if (initrd_start) {
614#ifdef CONFIG_BLK_DEV_RAM
615		int fd;
616		printk(KERN_INFO "Trying to unpack rootfs image as initramfs...\n");
617		err = unpack_to_rootfs((char *)initrd_start,
618			initrd_end - initrd_start);
619		if (!err) {
620			free_initrd();
621			goto done;
622		} else {
623			clean_rootfs();
624			unpack_to_rootfs(__initramfs_start, __initramfs_size);
625		}
626		printk(KERN_INFO "rootfs image is not initramfs (%s)"
627				"; looks like an initrd\n", err);
628		fd = sys_open("/initrd.image",
629			      O_WRONLY|O_CREAT, 0700);
630		if (fd >= 0) {
631			ssize_t written = xwrite(fd, (char *)initrd_start,
632						initrd_end - initrd_start);
633
634			if (written != initrd_end - initrd_start)
635				pr_err("/initrd.image: incomplete write (%zd != %ld)\n",
636				       written, initrd_end - initrd_start);
637
638			sys_close(fd);
639			free_initrd();
640		}
641	done:
642#else
 
643		printk(KERN_INFO "Unpacking initramfs...\n");
644		err = unpack_to_rootfs((char *)initrd_start,
645			initrd_end - initrd_start);
646		if (err)
647			printk(KERN_EMERG "Initramfs unpacking failed: %s\n", err);
648		free_initrd();
649#endif
650		/*
651		 * Try loading default modules from initramfs.  This gives
652		 * us a chance to load before device_initcalls.
653		 */
654		load_default_modules();
655	}
 
 
 
 
 
 
 
 
 
 
 
 
656	return 0;
657}
658rootfs_initcall(populate_rootfs);
v5.4
  1// SPDX-License-Identifier: GPL-2.0
 
 
 
 
 
 
 
 
 
  2#include <linux/init.h>
  3#include <linux/fs.h>
  4#include <linux/slab.h>
  5#include <linux/types.h>
  6#include <linux/fcntl.h>
  7#include <linux/delay.h>
  8#include <linux/string.h>
  9#include <linux/dirent.h>
 10#include <linux/syscalls.h>
 11#include <linux/utime.h>
 12#include <linux/file.h>
 13
 14static ssize_t __init xwrite(int fd, const char *p, size_t count)
 15{
 16	ssize_t out = 0;
 17
 18	/* sys_write only can write MAX_RW_COUNT aka 2G-4K bytes at most */
 19	while (count) {
 20		ssize_t rv = ksys_write(fd, p, count);
 21
 22		if (rv < 0) {
 23			if (rv == -EINTR || rv == -EAGAIN)
 24				continue;
 25			return out ? out : rv;
 26		} else if (rv == 0)
 27			break;
 28
 29		p += rv;
 30		out += rv;
 31		count -= rv;
 32	}
 33
 34	return out;
 35}
 36
 37static __initdata char *message;
 38static void __init error(char *x)
 39{
 40	if (!message)
 41		message = x;
 42}
 43
 44/* link hash */
 45
 46#define N_ALIGN(len) ((((len) + 1) & ~3) + 2)
 47
 48static __initdata struct hash {
 49	int ino, minor, major;
 50	umode_t mode;
 51	struct hash *next;
 52	char name[N_ALIGN(PATH_MAX)];
 53} *head[32];
 54
 55static inline int hash(int major, int minor, int ino)
 56{
 57	unsigned long tmp = ino + minor + (major << 3);
 58	tmp += tmp >> 5;
 59	return tmp & 31;
 60}
 61
 62static char __init *find_link(int major, int minor, int ino,
 63			      umode_t mode, char *name)
 64{
 65	struct hash **p, *q;
 66	for (p = head + hash(major, minor, ino); *p; p = &(*p)->next) {
 67		if ((*p)->ino != ino)
 68			continue;
 69		if ((*p)->minor != minor)
 70			continue;
 71		if ((*p)->major != major)
 72			continue;
 73		if (((*p)->mode ^ mode) & S_IFMT)
 74			continue;
 75		return (*p)->name;
 76	}
 77	q = kmalloc(sizeof(struct hash), GFP_KERNEL);
 78	if (!q)
 79		panic("can't allocate link hash entry");
 80	q->major = major;
 81	q->minor = minor;
 82	q->ino = ino;
 83	q->mode = mode;
 84	strcpy(q->name, name);
 85	q->next = NULL;
 86	*p = q;
 87	return NULL;
 88}
 89
 90static void __init free_hash(void)
 91{
 92	struct hash **p, *q;
 93	for (p = head; p < head + 32; p++) {
 94		while (*p) {
 95			q = *p;
 96			*p = q->next;
 97			kfree(q);
 98		}
 99	}
100}
101
102static long __init do_utime(char *filename, time64_t mtime)
103{
104	struct timespec64 t[2];
105
106	t[0].tv_sec = mtime;
107	t[0].tv_nsec = 0;
108	t[1].tv_sec = mtime;
109	t[1].tv_nsec = 0;
110
111	return do_utimes(AT_FDCWD, filename, t, AT_SYMLINK_NOFOLLOW);
112}
113
114static __initdata LIST_HEAD(dir_list);
115struct dir_entry {
116	struct list_head list;
117	char *name;
118	time64_t mtime;
119};
120
121static void __init dir_add(const char *name, time64_t mtime)
122{
123	struct dir_entry *de = kmalloc(sizeof(struct dir_entry), GFP_KERNEL);
124	if (!de)
125		panic("can't allocate dir_entry buffer");
126	INIT_LIST_HEAD(&de->list);
127	de->name = kstrdup(name, GFP_KERNEL);
128	de->mtime = mtime;
129	list_add(&de->list, &dir_list);
130}
131
132static void __init dir_utime(void)
133{
134	struct dir_entry *de, *tmp;
135	list_for_each_entry_safe(de, tmp, &dir_list, list) {
136		list_del(&de->list);
137		do_utime(de->name, de->mtime);
138		kfree(de->name);
139		kfree(de);
140	}
141}
142
143static __initdata time64_t mtime;
144
145/* cpio header parsing */
146
147static __initdata unsigned long ino, major, minor, nlink;
148static __initdata umode_t mode;
149static __initdata unsigned long body_len, name_len;
150static __initdata uid_t uid;
151static __initdata gid_t gid;
152static __initdata unsigned rdev;
153
154static void __init parse_header(char *s)
155{
156	unsigned long parsed[12];
157	char buf[9];
158	int i;
159
160	buf[8] = '\0';
161	for (i = 0, s += 6; i < 12; i++, s += 8) {
162		memcpy(buf, s, 8);
163		parsed[i] = simple_strtoul(buf, NULL, 16);
164	}
165	ino = parsed[0];
166	mode = parsed[1];
167	uid = parsed[2];
168	gid = parsed[3];
169	nlink = parsed[4];
170	mtime = parsed[5]; /* breaks in y2106 */
171	body_len = parsed[6];
172	major = parsed[7];
173	minor = parsed[8];
174	rdev = new_encode_dev(MKDEV(parsed[9], parsed[10]));
175	name_len = parsed[11];
176}
177
178/* FSM */
179
180static __initdata enum state {
181	Start,
182	Collect,
183	GotHeader,
184	SkipIt,
185	GotName,
186	CopyFile,
187	GotSymlink,
188	Reset
189} state, next_state;
190
191static __initdata char *victim;
192static unsigned long byte_count __initdata;
193static __initdata loff_t this_header, next_header;
194
195static inline void __init eat(unsigned n)
196{
197	victim += n;
198	this_header += n;
199	byte_count -= n;
200}
201
202static __initdata char *vcollected;
203static __initdata char *collected;
204static long remains __initdata;
205static __initdata char *collect;
206
207static void __init read_into(char *buf, unsigned size, enum state next)
208{
209	if (byte_count >= size) {
210		collected = victim;
211		eat(size);
212		state = next;
213	} else {
214		collect = collected = buf;
215		remains = size;
216		next_state = next;
217		state = Collect;
218	}
219}
220
221static __initdata char *header_buf, *symlink_buf, *name_buf;
222
223static int __init do_start(void)
224{
225	read_into(header_buf, 110, GotHeader);
226	return 0;
227}
228
229static int __init do_collect(void)
230{
231	unsigned long n = remains;
232	if (byte_count < n)
233		n = byte_count;
234	memcpy(collect, victim, n);
235	eat(n);
236	collect += n;
237	if ((remains -= n) != 0)
238		return 1;
239	state = next_state;
240	return 0;
241}
242
243static int __init do_header(void)
244{
245	if (memcmp(collected, "070707", 6)==0) {
246		error("incorrect cpio method used: use -H newc option");
247		return 1;
248	}
249	if (memcmp(collected, "070701", 6)) {
250		error("no cpio magic");
251		return 1;
252	}
253	parse_header(collected);
254	next_header = this_header + N_ALIGN(name_len) + body_len;
255	next_header = (next_header + 3) & ~3;
256	state = SkipIt;
257	if (name_len <= 0 || name_len > PATH_MAX)
258		return 0;
259	if (S_ISLNK(mode)) {
260		if (body_len > PATH_MAX)
261			return 0;
262		collect = collected = symlink_buf;
263		remains = N_ALIGN(name_len) + body_len;
264		next_state = GotSymlink;
265		state = Collect;
266		return 0;
267	}
268	if (S_ISREG(mode) || !body_len)
269		read_into(name_buf, N_ALIGN(name_len), GotName);
270	return 0;
271}
272
273static int __init do_skip(void)
274{
275	if (this_header + byte_count < next_header) {
276		eat(byte_count);
277		return 1;
278	} else {
279		eat(next_header - this_header);
280		state = next_state;
281		return 0;
282	}
283}
284
285static int __init do_reset(void)
286{
287	while (byte_count && *victim == '\0')
288		eat(1);
289	if (byte_count && (this_header & 3))
290		error("broken padding");
291	return 1;
292}
293
294static void __init clean_path(char *path, umode_t fmode)
295{
296	struct kstat st;
297
298	if (!vfs_lstat(path, &st) && (st.mode ^ fmode) & S_IFMT) {
299		if (S_ISDIR(st.mode))
300			ksys_rmdir(path);
301		else
302			ksys_unlink(path);
303	}
 
304}
305
306static int __init maybe_link(void)
307{
308	if (nlink >= 2) {
309		char *old = find_link(major, minor, ino, mode, collected);
310		if (old) {
311			clean_path(collected, 0);
312			return (ksys_link(old, collected) < 0) ? -1 : 1;
313		}
 
314	}
315	return 0;
316}
317
318static __initdata int wfd;
319
320static int __init do_name(void)
321{
322	state = SkipIt;
323	next_state = Reset;
324	if (strcmp(collected, "TRAILER!!!") == 0) {
325		free_hash();
326		return 0;
327	}
328	clean_path(collected, mode);
329	if (S_ISREG(mode)) {
330		int ml = maybe_link();
331		if (ml >= 0) {
332			int openflags = O_WRONLY|O_CREAT;
333			if (ml != 1)
334				openflags |= O_TRUNC;
335			wfd = ksys_open(collected, openflags, mode);
336
337			if (wfd >= 0) {
338				ksys_fchown(wfd, uid, gid);
339				ksys_fchmod(wfd, mode);
340				if (body_len)
341					ksys_ftruncate(wfd, body_len);
342				vcollected = kstrdup(collected, GFP_KERNEL);
343				state = CopyFile;
344			}
345		}
346	} else if (S_ISDIR(mode)) {
347		ksys_mkdir(collected, mode);
348		ksys_chown(collected, uid, gid);
349		ksys_chmod(collected, mode);
350		dir_add(collected, mtime);
351	} else if (S_ISBLK(mode) || S_ISCHR(mode) ||
352		   S_ISFIFO(mode) || S_ISSOCK(mode)) {
353		if (maybe_link() == 0) {
354			ksys_mknod(collected, mode, rdev);
355			ksys_chown(collected, uid, gid);
356			ksys_chmod(collected, mode);
357			do_utime(collected, mtime);
358		}
359	}
360	return 0;
361}
362
363static int __init do_copy(void)
364{
365	if (byte_count >= body_len) {
366		if (xwrite(wfd, victim, body_len) != body_len)
367			error("write error");
368		ksys_close(wfd);
369		do_utime(vcollected, mtime);
370		kfree(vcollected);
371		eat(body_len);
372		state = SkipIt;
373		return 0;
374	} else {
375		if (xwrite(wfd, victim, byte_count) != byte_count)
376			error("write error");
377		body_len -= byte_count;
378		eat(byte_count);
379		return 1;
380	}
381}
382
383static int __init do_symlink(void)
384{
385	collected[N_ALIGN(name_len) + body_len] = '\0';
386	clean_path(collected, 0);
387	ksys_symlink(collected + N_ALIGN(name_len), collected);
388	ksys_lchown(collected, uid, gid);
389	do_utime(collected, mtime);
390	state = SkipIt;
391	next_state = Reset;
392	return 0;
393}
394
395static __initdata int (*actions[])(void) = {
396	[Start]		= do_start,
397	[Collect]	= do_collect,
398	[GotHeader]	= do_header,
399	[SkipIt]	= do_skip,
400	[GotName]	= do_name,
401	[CopyFile]	= do_copy,
402	[GotSymlink]	= do_symlink,
403	[Reset]		= do_reset,
404};
405
406static long __init write_buffer(char *buf, unsigned long len)
407{
408	byte_count = len;
409	victim = buf;
410
411	while (!actions[state]())
412		;
413	return len - byte_count;
414}
415
416static long __init flush_buffer(void *bufv, unsigned long len)
417{
418	char *buf = (char *) bufv;
419	long written;
420	long origLen = len;
421	if (message)
422		return -1;
423	while ((written = write_buffer(buf, len)) < len && !message) {
424		char c = buf[written];
425		if (c == '0') {
426			buf += written;
427			len -= written;
428			state = Start;
429		} else if (c == 0) {
430			buf += written;
431			len -= written;
432			state = Reset;
433		} else
434			error("junk within compressed archive");
435	}
436	return origLen;
437}
438
439static unsigned long my_inptr; /* index of next byte to be processed in inbuf */
440
441#include <linux/decompress/generic.h>
442
443static char * __init unpack_to_rootfs(char *buf, unsigned long len)
444{
445	long written;
446	decompress_fn decompress;
447	const char *compress_name;
448	static __initdata char msg_buf[64];
449
450	header_buf = kmalloc(110, GFP_KERNEL);
451	symlink_buf = kmalloc(PATH_MAX + N_ALIGN(PATH_MAX) + 1, GFP_KERNEL);
452	name_buf = kmalloc(N_ALIGN(PATH_MAX), GFP_KERNEL);
453
454	if (!header_buf || !symlink_buf || !name_buf)
455		panic("can't allocate buffers");
456
457	state = Start;
458	this_header = 0;
459	message = NULL;
460	while (!message && len) {
461		loff_t saved_offset = this_header;
462		if (*buf == '0' && !(this_header & 3)) {
463			state = Start;
464			written = write_buffer(buf, len);
465			buf += written;
466			len -= written;
467			continue;
468		}
469		if (!*buf) {
470			buf++;
471			len--;
472			this_header++;
473			continue;
474		}
475		this_header = 0;
476		decompress = decompress_method(buf, len, &compress_name);
477		pr_debug("Detected %s compressed data\n", compress_name);
478		if (decompress) {
479			int res = decompress(buf, len, NULL, flush_buffer, NULL,
480				   &my_inptr, error);
481			if (res)
482				error("decompressor failed");
483		} else if (compress_name) {
484			if (!message) {
485				snprintf(msg_buf, sizeof msg_buf,
486					 "compression method %s not configured",
487					 compress_name);
488				message = msg_buf;
489			}
490		} else
491			error("invalid magic at start of compressed archive");
492		if (state != Reset)
493			error("junk at the end of compressed archive");
494		this_header = saved_offset + my_inptr;
495		buf += my_inptr;
496		len -= my_inptr;
497	}
498	dir_utime();
499	kfree(name_buf);
500	kfree(symlink_buf);
501	kfree(header_buf);
502	return message;
503}
504
505static int __initdata do_retain_initrd;
506
507static int __init retain_initrd_param(char *str)
508{
509	if (*str)
510		return 0;
511	do_retain_initrd = 1;
512	return 1;
513}
514__setup("retain_initrd", retain_initrd_param);
515
516#ifdef CONFIG_ARCH_HAS_KEEPINITRD
517static int __init keepinitrd_setup(char *__unused)
518{
519	do_retain_initrd = 1;
520	return 1;
521}
522__setup("keepinitrd", keepinitrd_setup);
523#endif
524
525extern char __initramfs_start[];
526extern unsigned long __initramfs_size;
527#include <linux/initrd.h>
528#include <linux/kexec.h>
529
530void __weak free_initrd_mem(unsigned long start, unsigned long end)
531{
532	free_reserved_area((void *)start, (void *)end, POISON_FREE_INITMEM,
533			"initrd");
534}
535
536#ifdef CONFIG_KEXEC_CORE
537static bool kexec_free_initrd(void)
538{
539	unsigned long crashk_start = (unsigned long)__va(crashk_res.start);
540	unsigned long crashk_end   = (unsigned long)__va(crashk_res.end);
 
 
 
541
 
542	/*
543	 * If the initrd region is overlapped with crashkernel reserved region,
544	 * free only memory that is not part of crashkernel region.
545	 */
546	if (initrd_start >= crashk_end || initrd_end <= crashk_start)
547		return false;
548
549	/*
550	 * Initialize initrd memory region since the kexec boot does not do.
551	 */
552	memset((void *)initrd_start, 0, initrd_end - initrd_start);
553	if (initrd_start < crashk_start)
554		free_initrd_mem(initrd_start, crashk_start);
555	if (initrd_end > crashk_end)
556		free_initrd_mem(crashk_end, initrd_end);
557	return true;
 
 
 
 
558}
559#else
560static inline bool kexec_free_initrd(void)
561{
562	return false;
563}
564#endif /* CONFIG_KEXEC_CORE */
565
566#ifdef CONFIG_BLK_DEV_RAM
567#define BUF_SIZE 1024
568static void __init clean_rootfs(void)
569{
570	int fd;
571	void *buf;
572	struct linux_dirent64 *dirp;
573	int num;
574
575	fd = ksys_open("/", O_RDONLY, 0);
576	WARN_ON(fd < 0);
577	if (fd < 0)
578		return;
579	buf = kzalloc(BUF_SIZE, GFP_KERNEL);
580	WARN_ON(!buf);
581	if (!buf) {
582		ksys_close(fd);
583		return;
584	}
585
586	dirp = buf;
587	num = ksys_getdents64(fd, dirp, BUF_SIZE);
588	while (num > 0) {
589		while (num > 0) {
590			struct kstat st;
591			int ret;
592
593			ret = vfs_lstat(dirp->d_name, &st);
594			WARN_ON_ONCE(ret);
595			if (!ret) {
596				if (S_ISDIR(st.mode))
597					ksys_rmdir(dirp->d_name);
598				else
599					ksys_unlink(dirp->d_name);
600			}
601
602			num -= dirp->d_reclen;
603			dirp = (void *)dirp + dirp->d_reclen;
604		}
605		dirp = buf;
606		memset(buf, 0, BUF_SIZE);
607		num = ksys_getdents64(fd, dirp, BUF_SIZE);
608	}
609
610	ksys_close(fd);
611	kfree(buf);
612}
613#else
614static inline void clean_rootfs(void)
615{
616}
617#endif /* CONFIG_BLK_DEV_RAM */
618
619#ifdef CONFIG_BLK_DEV_RAM
620static void __init populate_initrd_image(char *err)
621{
622	ssize_t written;
623	int fd;
624
625	unpack_to_rootfs(__initramfs_start, __initramfs_size);
626
627	printk(KERN_INFO "rootfs image is not initramfs (%s); looks like an initrd\n",
628			err);
629	fd = ksys_open("/initrd.image", O_WRONLY | O_CREAT, 0700);
630	if (fd < 0)
631		return;
632
633	written = xwrite(fd, (char *)initrd_start, initrd_end - initrd_start);
634	if (written != initrd_end - initrd_start)
635		pr_err("/initrd.image: incomplete write (%zd != %ld)\n",
636		       written, initrd_end - initrd_start);
637	ksys_close(fd);
638}
639#else
640static void __init populate_initrd_image(char *err)
641{
642	printk(KERN_EMERG "Initramfs unpacking failed: %s\n", err);
643}
644#endif /* CONFIG_BLK_DEV_RAM */
645
646static int __init populate_rootfs(void)
647{
648	/* Load the built in initramfs */
649	char *err = unpack_to_rootfs(__initramfs_start, __initramfs_size);
650	if (err)
651		panic("%s", err); /* Failed to decompress INTERNAL initramfs */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
652
653	if (!initrd_start || IS_ENABLED(CONFIG_INITRAMFS_FORCE))
654		goto done;
655
656	if (IS_ENABLED(CONFIG_BLK_DEV_RAM))
657		printk(KERN_INFO "Trying to unpack rootfs image as initramfs...\n");
658	else
659		printk(KERN_INFO "Unpacking initramfs...\n");
660
661	err = unpack_to_rootfs((char *)initrd_start, initrd_end - initrd_start);
662	if (err) {
663		clean_rootfs();
664		populate_initrd_image(err);
 
 
 
 
 
 
665	}
666
667done:
668	/*
669	 * If the initrd region is overlapped with crashkernel reserved region,
670	 * free only memory that is not part of crashkernel region.
671	 */
672	if (!do_retain_initrd && initrd_start && !kexec_free_initrd())
673		free_initrd_mem(initrd_start, initrd_end);
674	initrd_start = 0;
675	initrd_end = 0;
676
677	flush_delayed_fput();
678	return 0;
679}
680rootfs_initcall(populate_rootfs);